Dalrymple seems to think so, though I can’t tell if he’s being sarcastic. His experience certainly does make him skeptical of medical trials:
When I was working in Africa I read a paper that proved that intravenous corticosteroids were of no benefit in cerebral malaria. Soon afterwards I had a patient with that foul disease whom I had treated according to the scientific evidence, but who failed to respond, at least as far as his mental condition was concerned – which, after all, was quite important. To save the body without the mind is of doubtful value.
I gave the patient an injection of corticosteroid and he responded as if by miracle. What was I supposed to conclude? That, according to the evidence, it was mere coincidence? This I could not do: and I have retained a healthy (or is it unhealthy?) skepticism of large, controlled trials ever since. For in the large numbers of patients who take part in such trials there may be patients who react idiosyncratically, that is to say, differently from the rest.